With a continuously growing population, it is becoming increasingly difficult to meet the world's energy needs as well as to control carbon emissions to kerb greenhouse gas emissions that are considered responsible for global warming phenomena. These concerns have triggered a drive towards more efficient energy consumption in an attempt to reduce energy consumption.
One such area of concern is lighting applications, either in domestic or commercial settings. There is a clear trend towards the replacement of traditional incandescent light bulbs, which are notoriously energy inefficient, with more energy-efficient replacements. Indeed, in many jurisdictions the production and retailing of incandescent light bulbs has been outlawed, thus forcing consumers to buy energy-efficient alternatives, e.g. when replacing incandescent light bulbs.
A particular promising alternative is provided by solid state lighting (SSL) devices, which can produce a unit luminous output at a fraction of the energy cost of incandescent light bulbs. An example of such a SSL element is a light emitting diode.
WO 2011/132120 A1 discloses a lighting device and a method to manufacture such a lighting device. The inventive concept is based on manufacturing a lighting device on an at least partly flexible sheet assembly which is rolled into a tube, such that the light source of the lighting device is arranged within the tube. The flexible sheet assembly is arranged such that the tube provides a light mixing chamber and light exit surface for the lighting device.
However, a particular problem associated with such tubular lighting devices is that upon fracturing of the glass tube the exposed electrical components such as the SSL elements may still be live, which therefore poses the risk of serious injury or even death by electrical shock if the live components are touched by someone. Moreover, the assembly of such tubular lighting devices can be cumbersome, and the amount of time and effort required to insert the flexible sheet assembly into the tubular body may result in an undesirable increase in the manufacturing cost of the lighting device.